(1) Field of the Invention
This present invention pertains to a video signal detection system and detection method and in particular to a detection system and detection method for detecting received video signal type within video device.
(2) Description of the Prior Art
Currently, all video devices such as televisions, projectors, monitors, etc, mostly support several video signal types, for example, composite signal, s video signal, component signal, analog RGB signal, and DVI signal, etc. The video device provides automatic video signal searching function, to determine received video signal type for following appropriate displaying of the received video signal.
Please refer to FIG. 1. FIG. 1 shows a detection system according to a conventional detection system. A video device 2 comprises a detection system 4 capable of detecting received video signal type. The detection system 4 comprises a plurality of signal receivers (input pins and hot swap plugs) 6a, 6b, 6c, 8a and 10a correspondingly for video signals with different types, such as composite signal, s video signal, component signal, analog RGB signal, and DVI signal. Typically, video signal can further include a synchronizing signal and a data signal.
Composite input pin 6a, s video input pin 6b and component input pin 6c, which are individually corresponding to composite signal, s video signal, and component signal, are all disposed in the front end of a video decoder 6. Using a switch 602 located in the video decoder 6 is able to sequentially switch these signals (composite signal, s video signal, and component signal).
The video decoder 6 further includes an analog/digital converter 604 and a MCU 606. Analog/digital converter 604 converts the received signal from input pin 6a, 6b, and 6c to digital signal, then proceeding initial signal processing by the MCU 606 for later on signal sending to video decoder 6.
Moreover, the analog RGB signal is received through the hot swap plug 8a located in front end of an analog/digital converter 8, and converted to digital signal by the analog/digital converter 8, and then transmitted out of the analog/digital converter 8.
The DVI signal is received by a hot swap plug 10a located in front end of a TDMS receiver 10, and then transmitted out of the TDMS receiver 10.
The digital signals being transmitted out from video decoder 6, analog/digital converter 8 or TDMS receiver 10, are later sent to an image processor 12 for image processing. By that, the corresponding image of the video signal is thus able to be displayed.
In the conventional system and method for determining received video signal type, a detection module 14, which is usually a firmware, is further disposed to the rear end of image processor 12. Through interpreting the synchronizing signal in video signal, the types of video signal received can be identified by the detection module 14, which is helpful for following image processing by image processor 12.
As described above, the interpretation procedure of the rear end firmware format the detection module 14 of image processor 12 is going over following steps. First, from composite input pin 6a going through the video decoder 6, and later to the image processor 12, and through the route of the detection module 14 is for determining whether comprising the corresponding synchronizing signal. Then, from the s video input pin 6b going through the video decoder 6, and later to the image processor 12, and through the route of the detection module 14 is for determining whether comprising the corresponding synchronizing signal. And then, from the component input pin 6c going through the video decoder 6, and later to the image processor 12, and through the route of the detection module 14 is for determining whether comprising the corresponding synchronizing signal.
And later on, from the hot swap plug 8a going through the analog/digital converter 8, and later to the image processor 12, and through the route of the detection module 14 is for determining whether comprising the corresponding synchronizing signal. And then, from the hot swap plug 10a going through the TDMS receiver 10, and later to the image processor 12, and through the route of the detection module 14 is for determining whether comprising the corresponding synchronizing signal. The steps of the interpretation procedure described above are so complicated. If the detection of synchronizing signal is at the final step, it usually takes more than 10 seconds. A user could run out of their patient and doubt the product quality of the display device 2.
Therefore, an objective of the present invention is to provide a detection system and method for detecting received video signal type within video device for solving the problem described above.